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In order to identify antioxidant flavonoids from Lindera glauca Blume, we performed phytochemical analysis of L. glauca Blume heartwood and isolated eight flavonoids - lindeglaucol (1), lindeglaucone (2), cilicicone B (3), tamarixetin 3-O-α-L-rhamnoside (4), procyanidin A2 (5), cinnamtannin B1 (6), cinnamtannin D1 (7), and procyanidin A1 (8) - through repeated column chromatography over silica gel (SiO₂), octadecyl silica gel (ODS) and Sephadex LH-20. The chemical structures of compounds 1-8 were elucidated from spectroscopic data (NMR, IR and MS). The low-density lipoprotein oxidation inhibitory activities of the isolated compounds were evaluated in vitro by using the thiobarbituric acid reactive substances assay. Compounds 5-8 exhibited high inhibition activity, comparable to the positive control butyl hydroxyl toluene. Compounds 2 and 3 were slightly less active, while 1 and 4 expressed low activity.

From the heartwood of Lindera glauca Blume three new diarylpropanoids have been isolated and identifi ed, which were named lindeglaucol, lindeglaucone, and lindeglaucoside A. Chipped heartwood was extracted repeatedly with 80 % aqueous methanol (MeOH) at room temperature, and the concentrated methanolic extract was successively partitioned with ethyl acetate (EtOAc), n -butanol, and H 2 O. From the EtOAc fraction, three new diarylpropanoids and a known chalconoid were isolated through repeated column chromatography with silica gel, octadecyl silica gel, and Sephadex LH-20. The chemical structures of the compounds were elucidated by interpretation of extensive spectroscopic data such as nuclear magnetic resonance, fast atom bombardment mass spectroscopy, and infrared. In addition, a known chalconoid, cilicicone B, was isolated for the fi rst time from the heartwood of L. glauca .

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